A Research On Optimization Of Tool-path Of 2D Profile Milling With Constant Cutting Force

High efficiency,high precision and high intelligence have been the direction of development of CNC technology.It is an urgent and significant problem that improving the degree of automation level of CNC machine tools and optimizing various machining parameters.Machining parameters are the basic controlled variables in CNC machining,meanwhile,the optimization of machining parameters is the basis of optimization of CNC machining.CNC machining parameters include cutting parameters,tools parameters,process and tool-path,among them tool-path is the main factor that affects the quality and effectiveness of products.This paper is aimed to discuss the variable-curvature 2D profile milling.Based on the research of the cutter path algorithm and modeling,and optimize the tool-path.Cutting force of profile milling is maintained in a relatively stable state,better processing efficiency is guaranteed.In this paper,first of all,from the perspective of the contour milling geometric relationship,the change of material removal rate per unit time in line,concave arc,convex arc were analyzed.With engagement angle as the main factor which influence the material removal rate per unit time,the influence of outline of the radius of curvature and working engagement of the cutting edge to peak cutting force were obtained,and computing method of engagement angle in different outline of the radius of curvature and working engagement of the cutting edge were determined.On this basis,modifier formula of working engagement of the cutting edge was obtained.Secondly,based on the modeling of the micro element method,2D profile milling mechanical model is established,the relationship between the radius of curvature and working engagement of the cutting edge and peak cutting force is obtained.At the same time,variable-step algorithm with arc height tolerance and the pitch/equidistant curve offset algorithm were designed,and use MATLAB to compile the 2D variable curvature contour milling tool path optimization algorithm,aimed to reduce peak cutting force variable curvature contour milling in fluctuation.Finally,the milling force measurement experiments were established.Using the designed tool-path optimization algorithm of constant cutting force 2D profile milling to modify the tool-path of test workpiece,and made the tools cut along the tool-path before and after optimization.By collecting and analyzing the cutting forces in the two cutting processes,the effectiveness of the 2D algorithm of the constant cutting force profile milling path is proved.